A combine head is the structure mounted on the front of a combine harvester vehicle to gather crop materials, separate them from the ground, and convey them to a separating section typically disposed inside the vehicle itself.
Combine heads typically extend laterally across in front of the combine harvester vehicle itself a distance of 10 to 40 feet. Combine heads are typically supported on a 3 to 6 foot wide feeder house that extends forward from the front of the vehicle. Five to 15 feet of the combine head is cantilevered outward from each side of the feeder house.
Supporting this width of combine head on a narrow 3-6 foot width of feeder house requires that the frame of the combine head be extremely strong and stiff. Unfortunately, the stronger and stiffer the combine head is, the heavier it is, and the more force it applies against the ground. Impacts by the ground due to the inertial resistance of this large mass can damage the combine head or structures mounted on it that harvest crops.
Combine heads are typically constructed with a plurality of long beams that extend laterally from side to side across the entire combine. In one common prior art configuration, there is an elongated upper beam that extends across the top of the combine head, an elongated lower beam that extends across the bottom of the combine head directly below the upper beam, and an elongated row unit frame that extends across the bottom of the combine head forward of the lower beam and approximately at the same height. The row unit beam is typically coupled to the lower beam with several forwardly-extending brackets or gussets that are fixed at their forward ends to the row unit beam and at their rear ends to the lower beam.
Farm equipment manufacturers are under continuous pressure to increase the efficiency of their vehicles. Regarding combines, there is continuous pressure to increase the width of the combine head so it is able to harvest more rows of crop in a single pass. As the combine head is increased in width, however, all of the beams and other members that comprise its frame must be increased in size to handle the increased weight.
What is needed is an improved combine head frame that distributes forces in a manner that permits the frame members and the combine head generally to be reduced in weight.